package com.lujin.eduservice.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.lujin.eduservice.entity.EduChapter;
import com.lujin.eduservice.entity.EduVideo;
import com.lujin.eduservice.entity.chapter.ChapterVo;
import com.lujin.eduservice.entity.chapter.VideoVo;
import com.lujin.eduservice.mapper.EduChapterMapper;
import com.lujin.eduservice.service.EduChapterService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.lujin.eduservice.service.EduVideoService;
import com.lujin.servicebase.exceptionhandler.GuliException;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.security.GeneralSecurityException;
import java.util.ArrayList;
import java.util.List;

/**
 * <p>
 * 课程 服务实现类
 * </p>
 *
 * @author lujin
 * @since 2021-07-06
 */
@Service
public class EduChapterServiceImpl extends ServiceImpl<EduChapterMapper, EduChapter> implements EduChapterService {

    @Autowired
    private EduVideoService videoService;//注入小节service用于查询

    //课程大纲列表，根据课程id查询
    @Override
    public List<ChapterVo> getChapterVideoByCourseId(String courseId) {
        //1 根据课程id查询课程里所有的章节
        QueryWrapper<EduChapter> wrapperChapter=new QueryWrapper<>();
        wrapperChapter.eq("course_id",courseId);
        List<EduChapter> eduChapterList=baseMapper.selectList(wrapperChapter);
        //2 查询小节
        QueryWrapper<EduVideo> wrapperVideo=new QueryWrapper<>();
        wrapperVideo.eq("course_id",courseId);
        List<EduVideo> eduVideoList=videoService.list(wrapperVideo);
        //创建list集合，用于封装最终数据
        List<ChapterVo> finalList=new ArrayList<>();
        //3 遍历查询章节list集合进行封装
        //遍历查询章节list集合
        for (int i = 0; i < eduChapterList.size(); i++) {
            EduChapter eduChapter=eduChapterList.get(i);
            //eduChapter对象复制到ChapterVo中
            ChapterVo chapterVo=new ChapterVo();
            BeanUtils.copyProperties(eduChapter,chapterVo);
            //把chapterVo放到最终list集合
            finalList.add(chapterVo);

            //创建集合，用于封装章节的小节
            List<VideoVo> videoList=new ArrayList<>();
            //4 遍历查询小节list集合进行封装
            for (int m = 0; m < eduVideoList.size(); m++) {
                //得到每个小节
                EduVideo eduVideo=eduVideoList.get(m);
                //判断：小节的chapterID是否等于章节的id
                if (eduVideo.getChapterId().equals(eduChapter.getId())){
                    //进行封装
                    VideoVo videoVo=new VideoVo();
                    BeanUtils.copyProperties(eduVideo,videoVo);
                    //放到小节封装集合
                    videoList.add(videoVo);
                }
            }
            //把封装之后小节list集合，放到章节对象里
            chapterVo.setChildren(videoList);
        }
        return finalList;
    }

    //删除章节的方法
    @Override
    public boolean deleteChapter(String chapterId) {
        //根据chapterId章节id查询小节video表，若查询的到数据，不删除
        QueryWrapper<EduVideo> wrapper=new QueryWrapper<>();
        wrapper.eq("chapter_id",chapterId);
        int count = videoService.count(wrapper);
        //判断
        if (count>0){//查询出小节，不进行删除
            throw new GuliException(20001,"不能删除");
        }else {//删除
            int result = baseMapper.deleteById(chapterId);
            return result>0;
        }
    }

    //2 根据课程id删除章节
    @Override
    public void removeChapterByCourseId(String courseId) {
        QueryWrapper<EduChapter> wrapper=new QueryWrapper<>();
        wrapper.eq("course_id",courseId);
        baseMapper.delete(wrapper);
    }
}
